More Extreme Rain: Climate Extremes Index

Sep 12, 2018

By Climate Central

This summer has brought flooding rainfall to several parts of the U.S. Pennsylvania had its wettest summer on record, and the neighboring states of Maryland, Virginia, and West Virginia each had one of their 10 wettest summers on record. The warming climate enhances the water cycle, leading to more extreme rainfall. The NCEI Climate Extremes Index indicates a surge in the amount of precipitation in the U.S. from the heaviest 1-day events over the past 20 years.

With flooding in parts of the Mississippi Valley and a strong Pacific storm coming into the Northwest, we examined the trend in the number of days each year with heavy precipitation at 244 individual sites in the U.S. This expands our nationwide-averaged heavy precipitation analysis from earlier this year, complementing the 2017 Climate Science

Rivers continue to swell in the Ohio and Mississippi Valleys. More than 10 inches of rain fell last week in Arkansas and Louisiana. While the individual weather pattern may allow for heavy rain, the heaviest of this precipitation is increasing as the world warms from climate change.

This week on the Shum Show, Climate Central's Greta Shum looks at Peru's heavy downpours. Over the past month, Peru has received the equivalent of six years worth of rain, causing damages and deaths. Meanwhile, Arctic and Antarctic sea ice had record lows this year. See the long-term trend in sea ice on WXshift's Arctic sea ice climate indicator